Throttle and transmission interlock



Jan.'25, 1938. o. K. KELLEY THROTTLE AND TRANSMISSION INTERLOCK Filed Agg. 22, 1935 Patented Jan. 25, 1938 UNITED STATES PATENT y OFFICE THBOTTLE AND TRANSMISSION INTER- LOCK corporation of Maine Applicationl August zz, 1935, serial No. ames 5 Claims.

'Ihis invention relates to the control mechanism of a motor vehicle, and particularly to an linterlock between the gear shift mechanism and the engine fuel feed system whereby racing or 5 speeding of the engine is prevented during gear shifting operation. A .Y

In the operation of a motor vehicle having a clutchand change speed gearing, the shifting of gears should be done with the clutch disengaged and the engine running slowly, and inthe event the clutch is engaged too soon and simultaneously therewith the engine is speeded up, damage to the power transmission assembly is likely to resuit. The possibility of improper operation is increased when compressed air is employed for effecting gear settings due to the lag which occurs between the admission of air and the respense to pressure. To compensate for suchlag, which, incidentally, is most pronounced when the power plant is at the rear of the vehicle or otherwise removed from the operators forward position as is the case with certain large passenger coaches now in use, the operator must allow a suilicient time interval between his sequential manipulation of the manual control means. To guard against improper operation is the prim object of this invention. V

In its broad aspect, the invention consists of mechanism whereby engine acceleration is prevented during the shiftingoperation. This results in an idle engine speed until the gears are fully set and eliminates the imposition of damaging strain by the sudden application of severe stress upon .partially engaged parts.

For a better understanding of the invention reference should be had to the accompanying Idrawing wherein Figure 1 is a more or less diagrammatic layout illustrating a preferred embodiment of a throttle and transmission `interlock, and

Figure 2 is a detailed sectionalview o1' a circuit closing switch associated with'the change-speed device.

The gear. shift mechanism and the change speed gearing may be of a conventional type and the drawing illustrates only so much thereof as is necessary for an understanding of its operation. The change speed gearing through which power is transmitted between the engine and the road wheels is enclosed within the gear box or housing |fone side of which carries a cover plate 2 having a hollow housing 3 thereon. Within the hollow housing 3 is supported a rockable and shiftable shaft l by which the shift rails of the lcured on one end of the shaft 4 for the shifting vroperation. A series ofy air pressure lines or conchange speed gearing are individually selected and shifted. For this purpose the shaft 4 carries a depending arm (not shown) which upon rocking movement of the shaft l is brought into proper engagement with a selected rail and upon 5 axial movement of the shaft shifts the rail to set selected gears in drive relation for power transmission.

For the operation of the shaft 4, use is made of a conventional compressed Aair sytem which in- 10. cludes a piston cylinder 5 containing a/piston connected with the shaft for rocking the same, and a piston cylinder 6 containing a piston seduits 1 are shownconnected to opposite ends of the respective piston cylinders for conducting air under pressure thereto, and these several conduits run from` the operators station at the front of the vehicle for connection through suitable valving with the source of compressed air. The valving usually consists of a multiple valve, the manipulation of which introduces air into the conduits in certain predetermined combinations whereby the desired speed setting is effected as will be readily understood by those familiar with th art. l

At the end of the shaft 4 opposite to the piston cylinder B there are located a pair of drilled open- .,ings extending at right angles to each other, the' axial opening extending from the end oi' the rail to an intermediate point and having mounted therein an insulator sleeve 8 and the lateral opening having therein an insulator plug 9. An electrical cable or conductor lll extends through the sleeve 8 for connection to a contact pin Il in the plug il,` which pin terminates in the head I2 and a pointed contact tip I3. As shown in Figure 2, the point of the tip i3 is intended for engageu ment with a ball Il held in engagement therewith by a coil spring I5 enclosed within the sleeve I6, the inner end of which is spun over or interiorly flanged to provide a seat for the ball when thecontact element is out of engagement therewith. The opposite end of the spring bears against a stud I1 threaded into the sleeve and carrying a nut I8 and a washer I9 by which. aj conductor cable 20 is fastened to the stud and1 which also serves to mount the sleeve on an insulator cover plate 2| removably secured over an opening in the wall of the housing 3. An annular collar 22 on the sleeve provides an abutment for Vthe inner side of the closure 2| and `s also serves to secure in place a forked contact 55 member 23 which provides apair of inwardly extending spring prongs adapted for engagement with the contact head I2 as is indicated by the dotted lines in Figure 2. By this construction the I cablesl II) and 20 may be bridged for the flow of shaft 4 is shifted axially to positions whereby. selected gears are in proper drive relationships.

In other words, the spacing of theflngers from the neutral position of the shaft 4 corresponds to the extent of movement of the shaft in completing a shift andthe vfingers are sufficiently wide as to be engaged by the contact head I2 in all positions to which the shaft 4 may be rocked in the selection of a shift rail.' The cable 20, as shown in Figure l, is connected to one sideof a storage battery 24 or other suitable source of electric current, the other side-of which is grounded as at 25, While the cable III isjoined to a relay device 26 which in turn is grounded at 21. This circuit is energized whenever the wires I and 20 are bridged as before described, and energization of the relay 2B serves to open the switch blade. 28 which is also grounded through the connection 21.

This switchblade 28 controls a circuit arranged l in parallel to that before described,.and contains an electrically operated valve 29 including a solenoid 30 connected with 'the battery by the conductor'3I and by the conductor 32 with the contact device for the switch blade 28. l

v- Energization of the solenoid 30 serves to open the valve 29 and allows air or other suitable fluid under. pressure to now from the source of supply through the conduit 133 and the conduit 34 to a fluid pressure device including the cylinder 35 and a piston 36 within the cylinder. A coil spring N serves to return the piston to normal position after fluid pressure is relieved and the limit. of the return movement is established by theA engagement of the end of the piston rod 38 with the end wall of the cylinder 35. The opposite end of the rod 38 .extends through the cylinder and is pivotally connected with a floating lever 39, the opposite end of which is joined by al link 4Il with a foot accelerator pedal 4I. Intermediate its ends the lever 39 is provided with a laterally extending pin 42 slidable within an elongated opening 43 in the vend of a link 44 adapted for connectionA with the throttle operating arm 45 of the carburetor 4G. A coil spring 41 or the likel may be provided to return the throttle to closed position when foot pressure on the pedal 4 Il is relieved.

when the parts referred to are in the fun une .position illustrated in the drawing it will be apparent that depression of the pedal l4I will swing the -le'ver '39 about its pivotal connection with the engine throttle remains in closed position and theV vpossibility of racing the engine .is' therefore:

eliminated.

From the above description it willbe seen that there has been provided an interlock whereby regardless of the inexperience or carelessness of an operator,the engine cannot be speeded up dur- 'ing the gear shifting operation. After the gears are fully set the vehicle may be operated in the usual fashion. In any speed setting the contact head I2 engages with one or the other of the contact vfingers depending upon vthe direction in which the shaft 4 is shifted to bring the gears in driving relation, and the contact I3 engages the ball I only in the neutral position of the parts. This last mentioned circuit closing expedient is provided inasmuch as it is sometimes desirable to open the throttle while the vehicle is not in motion.

While the above description has been more or less specific, the invention is not limited to the exact details referred to and it is to be understood that such modifications may bemade as come within the appended claims.'

I claim:

l. The combination with engine throttle actuating linkage having a lost motion connection and selective' speed gear vsetting mechanism, of a iiuid pressure actuated device controlling the action of said lost motion connection, an electrically actuated valve controlling fluid pressure y supply to said device, and means associated with the selective speed gear setting mechanism controlling the flow of electric current in the circuit containing -said electrically actuated valve in accordance with predetermined settings of said mechanism.

2. The combination with variable speed gear setting mechanism and the fuel feed system of an engine, of an'electricaliy actuated device adapted .to limit operation of the fuel feed system, and circuit closing means `associated with the gear setting mechanism to direct current to said device when the mechanism is positioned in predeteroperated means controlling said system, a pressure responsive device to free the system from manual `control, operating connections between said device and'the manually operated means, means to supply operating pressure to said device, an electrically operated valve controlling the application of pressure to lsaid device, a change speed shifter movable between stations and switch,

means dependent upon shifter position to supply electric current for operating said valve.

4. I n a motor vehicle, means to prevent acceleration of an engine during operations of changing transmission gear settings, including ai manually controlled engine fuel feed system', a change speed shifter movable between a gear setting station and a neutral station,l means operably connected with said system to free Vthe same fi'rom manual control, and means under control of the speed shifter to operate the first-named means, said-second named means being conf n structed and arranged to be brought into action duringtravel-of the shifter between said stations `and'to be cut out oi' action by the-setting of the shifter in setting station.

either theneutral station or the gear 5. In a motor vehicle, means to prevent engine under control oi' the shifter and active only duracceleration while making changes of gear seting travel of the shifter between said stations to tings, including a manually controlled engine fuel operate said iirst mentioned means, the said menfeed system, a change speed shifter movable betioned means being inactive when the shifter is in 5 tween a neutral station and a gear setting station, either of said stations.

means operably connected with said system to free the same from manual control, and means omen K. mmm.

v CERTIFICATE 0F CORRECTION. Patent No. 2,106,607. January 25, i958.

OLIVER K. KELLEY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 50, claim5, after v"means" insert the word normally; page 5, second column, line'g, claim 5, after "said" second occurrence, :insert the word second; and that the said Letters Patent should be read with these corrections therein that the -same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of March, A.l D. 1958.

A Henry Van Arsdale, A(Seal) Acting Commissioner of Patents.

5. In a motor vehicle, means to prevent engine under control oi' the shifter and active only duracceleration while making changes of gear seting travel of the shifter between said stations to tings, including a manually controlled engine fuel operate said iirst mentioned means, the said menfeed system, a change speed shifter movable betioned means being inactive when the shifter is in 5 tween a neutral station and a gear setting station, either of said stations.

means operably connected with said system to free the same from manual control, and means omen K. mmm.

v CERTIFICATE 0F CORRECTION. Patent No. 2,106,607. January 25, i958.

OLIVER K. KELLEY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 50, claim5, after v"means" insert the word normally; page 5, second column, line'g, claim 5, after "said" second occurrence, :insert the word second; and that the said Letters Patent should be read with these corrections therein that the -same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of March, A.l D. 1958.

A Henry Van Arsdale, A(Seal) Acting Commissioner of Patents. 

